Apparatus and method for forming flashings for roof vent pipes

ABSTRACT

A flashing for protecting the junction intermediate a roof vent pipe and the surrounding roof surface is disclosed. A method for forming the flashing is also described.

United States Patent Clement July 22, 1975 [54] APPARATUS AND METHOD FOR FORMING 2,300,842 11/1942 Leslie 52/199 X FLASHINGS FOR ROOF VENT PIPES 3,524,400 8/1970 Magi 98/64 X [75] Inventor: Clyde H. Clement, Phoenix, Ariz.

[73] Assignee: Lester E. Kron, Phoenix, Ariz.

[22] Filed: Nov. 21, 1973 211 App]. No.: 417,791

[52] US. Cl. 52/199; 52/60; 98/42; 93/122 [51] Int. Cl. E04h 12/28 [58] Field of Search 52/199, 58, 60; 98/42, 98/61-64, 122

[56] References Cited UNITED STATES PATENTS 853,897 5/1907 Porter 52/58 X FOREIGN PATENTS OR APPLICATIONS 1,218,490 1/1971 United Kingdom 98/122 615,327 2/1961 Canada ..52/199 Primary Examiner.l. Karl Bell Attorney, Agent, or FirmCahi1l, Sutton & Thomas [57] ABSTRACT 7 Claims, 11 Drawing Figures APPARATUS AND METHOD FOR FORMING FLASHINGS FOR ROOF VENT PIPES The present application pertains to and arises from material submitted to the U.S. Pat. Offlce on Mar. 8, 1972, and identified as Disclosure Document No. 009464.

The present invention relates to flashings, and, more particularly, to flashings and a method for making the same to protect the junction intermediate a roof and vent pipes extending therefrom against the elements.

Commercial buildings and private dwellings usually include a plurality of pipes extending through the roof and venting to the atmosphere. These vent pipes may be connected to the plumbing system of the building or dwelling to prevent air locks and pressure buildups. In the more modern buildings and dwellings, additional vent pipes may be connected to air exhaust systems, located within the kitchen and/or the bathrooms.

The junction between the vent pipes and the roof must be adequately sealed to prevent water seepage along the pipe with the attendent damage to the roof or rooms below. The most common means for sealing the vent pipe to the roof is that of circumscribing the vent pipe with a frusto conically shaped flashing. The lower end of the flashing is sealed to the roof and the upper end of the flashing is sealed to the vent pipe. The following United States Patents illustrate various examples of the above described flashings used in conjunction with a sloping roof: Nos. 506,930, 580,515, 1,279,572, 1,511,844 and 3,602,530.

Although it is a relatively simple matter to seal the flashing to the roof by employing a flange about the base of the flashing, it is quite difficult to seal the flashing to the vent pipe. As a result, a substantial amount of work has been done in developing sealing members for engaging both the upper extremity of the flashing and the circumscribed vent pipe. U.S. Pat. Nos. 1,244,750 and reissue 26,026 are representative of efforts made in this direction.

Despite the amount of work previously done to improve and perfect upon vent pipe flashings, several serious problems still remain. ln geographical regions where there are wide temperature changes over a short period of time, the difference in thermal expansion and contraction of the vent pipe, the flashing and the sealing member (if used) tends to deteriorate or break the seal intermediate the flashing and the vent pipe. The seal intermediate the base of the flashing and the shingles or tiles of a sloping roof is generally preserved by the overlapping relationship of the shingles or tiles with the base of the flashing.

Another cause of leakage intermediate the junction between the vent pipe and the roof results because of settling in new houses. Because a settling of the framework of the house, including relief of stresses formed therein during the building of the house. may be different from that of the plumbing system or the air exhaust system, movement of the vent pipes with respect to the roof may occur, which movement tends to break any weather seals intermediate the vent pipe and the flash- In the presently used flashings, the opening in the core of the flashing is configured to accommodate a vent pipe of a particular diameteizAlthough substantial efforts have been made to standardize the diameter of vent pipes. such standardization has not yet been accomplished. Therefore, many differently sized flashings must be made to accommodate each of the differently sized vent pipes. The resulting manufacturing requirement placed upon the manufacturer tends to increase the overall cost of the flashing. In addition, the supplier, whether wholesale or retail, must stock a substantial variety of flashings to satisfy the needs of his customers. The flashings are generally bulky and require a lot of storage space. This storage space requirement, in combination with a number of different flashings, presents a substantial storage expense to both the wholesaler and retailer.

It is therefore a primary object of the present invention to provide a single flashing useable in conjunction with a wide range of vent pipe sizes.

Another object of the present invention is to provide a flashing for roof vent pipes which inhibits water seepage adjacent the vent pipe despite relative movement between the vent pipe and the roof.

Yet another object of the present invention is to obviate the need for sealing a vent pipe to its flashing.

Still another object of the present invention is to provide a flashing useable in conjunction with either metallic or plastic vent pipes.

Still another object of the present invention is to provide nestable flashings.

A further object of the present invention is to provide a process for for producing flashings with automated machinery.

A yet further object of the present invention is to provide a method for forming a flashing for vent pipes from a single section of sheet metal.

A still further object of the present invention is to provide a method for forming flashings for either flat or slanted roofs.

These and other objects of the present invention will become apparent to those skilled in the art as the description thereof proceeds.

The present invention may be described with greater specificity and clarity with reference to the following drawings, in which:

FIG. 1 illustrates the present invention mounted upon a slanted roof of a dwelling.

FIG. 2 illustrates a cross-sectional view of the present invention taken along lines 2-2, as shown in FIG. 1.

FIG. 3 illustrates a perspective view of the present invention.

FIG. 4 illustrates the steps in the manufacturing process for producing the present invention.

FIG. 5 illustrates a cross-section of one of the dies used in the manufacturing process, taken along lines 5-5 as shown in FIG. 4.

FIG. 6 illustrates a cross-sectional view of the flashing produced by the manufacturing process ofthe present invention, taken along lines 6-6 as shown in FIG. 4.

FIG. 7 illustrates a further cross-sectional view of the flashing produced by the manufacturing process of the present invention, taken along lines 7-7 as shown in FIG. 4.

FIG. 8'illustrates the nesting of the present invention.

FIG. 9 illustrates the manufacturing process of the present invention for producing a flashing useable on flat roofs.

FIG. 10 illustrates a cross-section of a flashing, taken along lines 10-10 as shown in FIG. 9.

FIG. 11 illustrates a further cross-section of the end product of the manufacturing process shown of a flashing, taken along lines I111 as shown'in FIG. 9.

Referring to FIG.. I, there is shown a dwelling 1 having a peaked roof 2. The roof may be covered withv as-- phalt shingles 4 as shown with regard to side 3 of the roof. The flashing 10 of the present invention is mounted upon side 3 of roof 2 and forms a cover over vent pipe may terminate in a plane defined by the external surface of side 3, as shown, or it may protrude upwardly therefrom. I

Flashing 10 is formed as a raised rectangular shaped protrusion 14. One end 15 of protrusion 14 is open while the opposite end is closed by means of slanting side 16. The lateral sides 17 and 18 extend upwardly from the base of flashing l and slant inwardly. The base of flashing is formed by a single flange'extending laterally outwardly from the three upwardly extending sides of protrusion 14. For descriptive purposes, the section of the flange adjacent side 18 is identified by numeral 11, the section of the flange adjacent side 16 is identified by numeral 13 and the section of the flange adjacent side 17 is identified by numeral 12.

Flashing 10 is mounted upon the roof 2 such that protrusion 14 receives the upper end of vent pipe 6, whether or notthe latter protrudes above the roof. The open end of flashing 10 is directed downwardly along the slope of the roof and is mounted such that the top surface 19 of protrusion 14 at least overlaps the edge of vent pipe 6. The flanges ll, 12 and 13 of flashing 10 may be mechanically secured to the roof by nails or screws. A weather tight seal intermediate the flashing and the roof is effected by overlapping the flanges with shingles 4, as shown by the phantom lines in FIG. I.

From the above description of the mounting of flashing 10, it may be understood that asphalt shingles 4 will prevent run-off water from penetrating intermediate the flanges of the flashing 10 and roof 2. Thereby, a good weather seal is effected between the flashing and the roof. As open end 15 is below the lower edge of vent pipe 6, it will shield the vent pipe and the adjacent area and prevent run-off water from seeping intermediate the vent pipe and the roof or into the vent pipe.

As illustrated by arrows 20 in FIG. '2, any air flowing out of vent pipe 6 flows into the chamber defined by protrusion 14 and escapes through open end 15. Should a vacuum be formed within the plumbing system associated with vent pipe 6, air would flow into the vent pipe in a direction reverse to that shown by the arrows.

It may be noted that the present invention does not require that the vent pipe extend upwardly from the roof. Thus, savings may be effected by using shorter vent pipes in buildings and dwellings. Further, it is unnecessary to employ mastic or other sealing compounds to seal the flashing to the vent pipe, as required in the prior art devices. Thereby, the present invention eliminates the cost of such mastic or sealing corn-v pounds and obviously eliminates any otherwise necessary labor costs.

Because-the flashings 10 do not have to be interconnected with the-,vent pipes in the ;manner.;of,theprior art devices, it becomes practicalto mak a single flashing which may be used with a wide range of vent pipes.

In example, one. size flashing may be made to accommodate vent pipes up to four inches in diameter and an. other size to accommodate vent pipes up to eight inches. This feature allows the number of. sizes of flashings to be kept to a minimum with resulting economy in manufacture and storage costs.

The prior art flashings,. as illustrated in the above cited patents, are generally formed by afrusto conically shaped member secured to a flange. A device of this type generally requires at least three basic manufacturing processes. First, the cone must be formed. Secondly, the flange for attaching the flashing to the roof mustbe formed with a hole of sufficient size to receive the base of the cone. Thirdly, the cone must be mated with the flange. For items such as flashings, where the cost must be kept extremely low, any and all manufacturing steps must be minimized and where ever possible must be automated to reduce the labor costs. The prior devices almost always included some labor costs, usually involving the mating of the cone with the flange.

The process of the present invention, isillustrated in FIG. 4, and completely obviates the need for any labor costs. Further, it permits the complete formation of a plurality of flashing from a roll of sheet metal.

A roll of sheet metal 25 is suitably mounted to feed a ribbon of sheet metal 24 to a progressive die. At the firststage or step of the die, a section 23 of the ribbon 24 is formed into what is known in the trade as a hat. The hat 28 is formed by a male die 26 mating with female die 27. It may be noted that the longitudinal sides of both dies 26 and 27 slope inwardly and upwardly.

At the second stage or step of the progressive die, a mandrel 29 is inserted within hat 28. Mandrel 29 is similar in cross-section to hat 28 but is not fully coextensive with the hat. It is terminated by downwardly sloping side 31. A female die 30, as shown in longitudinal cross-section in FIG. 5, is similarly configured to include a cavity 22 having a lateral cross-section to that of the outer dimensions of hat 28. The length of cavity 22 is less. than the length of hat 28. Cavity 22 is terminated by a downwardly and sloping side 32. The lengths of both the mandrel 29 and cavity 22 are essentially equal, except that the cavity is longer by an amount equivalent to the thickness of the ribbon 24.

After the mandrel 29 is inserted within hat 28, the female die 30 is lowered upon the hat. As the female die 30 is lowered, the part of hat 28 not corresponding to cavity 22 of the female die will be crushed and flattened, as represented by numeral 33. Simultaneously with the lowering of female die 30, the metal adjacent the longitudinal sides of hat 28 are clamped or otherwise retained in position to prevent buckling and distortion of the metal along the sides of hat 28. The clamping of the metal also tends to prevent distortion of the remaining upstanding part of hat 28.

At the next stage or step of the progressive die, each of the products or flashings 10 formed by the first and second steps is severed by means of a cutting element such as knife 34. The point at which the sections 23 containing the flashings are severed from one another is indicated by the dashed lines extending transverse to the ribbon 24. It is to be understood that the roll 25 of sheet metal may be initially cut'into a plurality. of sec tions with each section being actedvupon by the progressive die.

FIGS. 6 and 7 illustrate cross-secti'o'nal-views of the end product produced by the process described in FIG. 4. From these figures, it may be noted that the flange l3 (identified in FIG. 4 as crushed section 33) is generally parallel to and in alignment with the undisturbed lateral flanges 11 and I2. Thereby, these surfaces will easily mate with the flat surface of the roof of a building. In addition, they extend outwardly from protrusion 14 by a sufficient amount to permit the roofing material, such as asphalt tile, to overlap them and form a good weather seal.

It may be noted that sides l6, l7 and 18 slope inwardly and upwardly and that top surface 19 is essentially parallel with flanges ll, 12 and 13. These features permit flashing to be nested as shown in FIG. 8. Thereby, a plurality of flashings may be contained within a relatively small storage space.

With the process of the present invention, it may be appreciated that the flashings 10 do not have any seams which might be sprung. Further, flashings 10 do not have any raw edges which are ungalvanized. Thereby, the useful life of the flashings is substantially extended.

Some private dwellings or commercial buildings are built with a flat roof instead of a peaked one as shown in FIG. 1. The flashing 10 described above cannot be used with such flat roofs without danger of water flowing in through open end and into or about the vent pipe. By modifying the previously described flashing to a limited extent, the basic principles and advantages of the previously described flashing may be preserved and yet render it suitable for use with vent pipe extending from a flat roof.

The process for forming the modified flashing 50 is illustrated in FIG. 9. A roll of sheet metal 35 is suitably mounted to feed a ribbon of metal 36 to a progressive die. The first stage of the progressive die includes a male and female die 37 and 38 respectively. These dies deform successive sections 39 of the ribbon 36 into a hat shaped configuration 40. It may be noted that the sides of hat 40 transverse to the ribbon 36 slant upwardly and inwardly.

The second stage of the progressive die includes a mandrel 41 equal in cross-sectional configuration to hat 40 but terminating short of the lateral edges of ribbon 36 by inwardly and upwardly sloping sides. The mandrel is inserted within hat 40. A mating female die 42 includes a cavity (not shown) equivalent of that of mandrel 41 but of a width and length greater than that of the mandrel by an amount equal to twice the thickness of the sheet metal. When the female die 42 is lowered upon hat 40 and the inserted mandrel 41, the extremities of the hat will be crushed, as indicated by crushed sections 43 and 44. The remaining protrusion 45 of hat 40 will be essentially equivalent to that of mandrel 41.

The next stage of the progressive die includes male and female die cutting members 46 and 47. These members out a hole 54 within the upper horizontal surface 51 of protrusion 45. The size of the hole is primarily dependent upon the diameter of the vent pipe to be protected by the flashing 50.

After the holes have been cut in the formed flashings 50, each of sections 39 are severed from the ribbon 36 by a knife 48. The line at which the sections 39 are severed is generally indicated by dotted lines identified by numeral 49: 1

Referring jointly to FIGS. 10 and 11, there are shown the cross-sections of the flashing produced by the process shown in FIG. 9. The protrusion 45 of flashing 50 is formed by upwardly and inwardly extending longitudinal sides 52 and 53 terminating at top surface 51. The top surface 51 includes an aperture 54 for receiving a vent pipe. Flanges 43 and 44, formed by the crushing of a section of hat 40, define the longitudinally extending flanges of flashing 50. The lateral sides of flashing 50 are formed by upwardly and inwardly extending sides 55 and 56. Flanges 57 and 58 extend lateral to sides 55 and 56. As may be surmised, flanges 57 and 58 include crushed sections 43 and 44, which are essentially parallel thereto and disposed in the same plane. Thereby, these flanges and sections will readily mate with the flat surface of a flat roof.

The inwardly slanting sides of flashings 50 permit the flashing to be nested for storage purposes, as shown for flashings 10 in FIG. 8.

While the principles of the invention have now been made clear in an illustrative embodiment, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components, used in the practice of the invention which are particularly adapted for specific environments and operating requirements without departing from those principles.

I claim:

1. A nestable vented roof mounted flashing for shielding an aperture disposed in a roof to prevent the intrusion of water through the aperture, said flashing comprising in combination:

a. a protrusion for covering the aperture, said protrusion being formed of a single piece of material and including:

1. a plurality of serially joined sides for for partially circumscribing the aperture, each of said sides extending upwardly to define a vertical space, each of said sides sloping inwardly and generally toward one another to accommodate nesting of a plurality of said flashings;

2. a cover supported by and extending intermediate the upper edges of said sides for shielding the aperture;

3. a vent for providing fluid communication between the aperture and the atmosphere surrounding said flashing, said vent being defined by the space intermediate the vertical extremities of the serially joined sides; and

b. a flange formed as a unitary element of said protrusion for attaching said flashing to the roof, said flange extending laterally outwardly from the lower edge of each of said sides.

2. The flashing as set forth in claim 1 wherein said protrusion and said flange are formed in a single piece v of sheet metal.

, 3,895,467 7 f v. i 6; The-flashing as set forth in claim ,wherein the ri'nieter-of said vent is defined by thevertical edges of lower edges of said sides define a plane parallel to the two non-joined ones of said sides, a lateral edge of said plane defined by the upper edges of said sides. cover and the roof. 1 J v 7. The flashing as set forth in claim 4 wherein the pe-- i a l 5 

1. A nestable vented roof mounted flashing for shielding an aperture disposed in a roof to prevent the intrusion of water through the aperture, said flashing comprising in combination: a. a protrusion for covering the aperture, said protrusion being formed of a single piece of material and including:
 1. a plurality of serially joined sides for for partially circumscribing the aperture, each of said sides extending upwardly to define a vertical space, each of said sides sloping inwardly and generally toward one another to accommodate nesting of a plurality of said flashings;
 2. a cover supported by and extending intermediate the upper edges of said sides for shielding the aperture;
 3. a vent for providing fluid communication between the aperture and the atmosphere surrounding said flashing, said vent being defined by the space intermediate the vertical extremities of the serially joined sides; and b. a flange formed as a unitary element of said protrusion for attaching said flashing to the roof, said flange extending laterally outwardly from the lower edge of each of said sides.
 2. a cover supported by and extending intermediate the upper edges of said sides for shielding the aperture;
 2. The flashing as set forth in claim 1 wherein said protrusion and said flange are formed in a single piece of sheet metal.
 3. The flashing as set forth in claim 2 wherein said sides comprise three sides.
 3. a vent for providing fluid communication between the aperture and the atmosphere surrounding said flashing, said vent being defined by the space intermediate the vertical extremities of the serially joined sides; and b. a flange formed as a unitary element of said protrusion for attaching said flashing to the roof, said flange extending laterally outwardly from the lower edge of each of said sides.
 4. The flashing as set forth in claim 3 wherein the lower edges of said three sides define three sides of a rectangle and the lower boundary of said vent defines the forth side of the rectangle.
 5. The flashing as set forth in claim 4 wherein said flange extending about said protrusion defines a U-shaped element.
 6. The flashing as set forth in claim 5 wherein the lower edges of said sides define a plane parallel to the plane defined by the upper edges of said sides.
 7. The flashing as set forth in claim 4 wherein the perimeter of said vent is defined by the vertical edges of two non-joined ones of said sides, a lateral edge of said cover and the roof. 